Article 48 of the law 5/2014.
1. Private investigation services, in charge of private detectives, They consist of the completion of the inquiries that are necessary for obtaining and contribution, authorized third parties, information and evidence on behaviors or private facts relating to the following aspects:

to) Those relating to the economic sphere, labour, commercial, financial and, in general, to personal life, family or social, except that develops in the homes or reserved places.

b) Obtaining information which aims to ensure the normal development of the activities that take place at fairs, Hotels, exhibitions, shows, contests, conventions, superstores, local public of big turnout or similar areas.

c) Carrying out inquiries and obtaining information and evidence concerning only prosecutable offences to request custom-made subjects legitimized in the criminal process.

2. The acceptance of the assignment of these services by the offices of private detectives will require, in any case, accreditation, by the applicant of the same, of the allegedly legitimate interest, What shall be recorded in the record of hiring and research that opens.

3. In no event is may investigate the private lives of people passed on their homes or other places reserved, or they may be used in this type of services personal media, material or technical ways that infringe upon the right to honour, personal or family privacy or image or the secrecy of communications or data protection.

4. In the provision of research services, private detectives may not use or make use of media, vehicles or badges that may be mistaken for those of the forces and security bodies.

5. In any case, the offices of detectives and private detectives responsible for investigations shall ensure the rights of its customers with respect of the investigated subjects.

6. Private investigation services will be carried out with respect for the principles of reasonableness, need, suitability and proportionality.